Tuesday, June 26, 2012

The first day of summer/longest day of the year for 2012 has come
and gone and just this past week a new National Drought Monitor Map was
published (see below). The city of West Lafayette in Tippecanoe County
has now fallen into the “Severe Drought” category. In fact 36% of Indiana is
now in severe drought, while > 5% (the southwestern counties) are now in
“extreme drought”.

Frankly, if you have been paying attention to landscape
conditions, it doesn’t take an expert to declare it a severe drought out there.
The overall appearance of unirrigated lawns and most turf areas is straw brown
and dormant with a “crunchy” leaf canopy. Many of these areas have been that
way for several weeks now.

This newer lawn is very "dormant", the small
green areas are patches of tall fescue that are still surviving and green.

The dry conditions combined with typical “above average”
summer temperatures, > 90 F, have led to a number of people contacting us
and asking… “Is my lawn dead?” The answer to this question is complicated, and
honestly, it is difficult to truly tell until many of these areas fully
rehydrate. Regardless, we are clearly pushing the edge of the envelope on
what many turfgrass species can tolerate. Some of our weaker cool-season lawn
grasses like the ryegrasses, annual bluegrass and roughstalk bluegrass (See
Images) are most likely not to recover. Other common turfgrasses like Kentucky
bluegrass or the fescues are more likely to survive. If you are fortunate
to have a warm-season lawn (e.g. zoysiagrass or bermudagrass) these lawns are
likely not dead.

This finer textured patch of turf above is most likely roughstalk
bluegrass it will look "dead" but may actually recover, there are
still some green shoots.

The other issue to consider is the maturity of the turf and
growing environment. Well maintained, mature lawns with a deep root system will
be faring much better than recent plantings. Furthermore, turf growing in
severely compacted soils or very coarse textured sandy soils may really
struggle and not recover. The driving factors for survival during severe
drought have to do with rooting depth and the “reservoir” of available water.
Sandy soils have less reserve water than fine textured soils and will need more
supplemental irrigation.

Now what???

A friend recently asked me recently what to do about their lawn
during these very dry conditions. I told them, honestly we will really just
need to wait and see. I told him if he has not been irrigating and the lawn is
brown then the plant is likely doing it’s best to conserve moisture during this
“survival mode”, protecting the crown or growing point. He said, “So I should
just accept “a little bit of brown?”, I responded “accept a whole lot of
brown!”

Should I water my lawn?

If you have been regularly watering your lawn you should continue,
the turf has been conditioned to this practice and shutting off the water may
be damaging to survival. Remember the rule of thumb for lawn irrigation is to
“water deeply and infrequently”. In other words, you should not be watering
lawn grasses every day but every 3 days or so.

On the other extreme, if you have not been watering your lawn it
is probably not worth starting at this point. Allow the turfgrass to remain
dormant. There is no guarantee that your lawn will survive these conditions of
2012, but… heavily watering at this time may actually shift the competitive
edge toward some of the warm-season grassy (e.g. crabgrass, etc.) and broadleaf
weeds that thrive during the summer months. Furthermore, the amount of water to
help the turf recover and then continue to sustain healthy growth may be cost
prohibitive. Allow the turf to remain dormant, some grasses like Kentucky
bluegrass have a dormancy mechanism and regrowth may occur from underground
stems/rhizomes when more favorable weather returns. If you feel like you need
to do something... applying about ½ inch of water every few weeks to keep the
crown alive and hydrated. This will help down the road. The turf leaves will
not turn green, but this practice will increase the chance for future survival.

Light irrigation may help this dormant Kentucky bluegrass survive

Will my lawn recover?

While many lawns might not be “dead”, one major factor that will
kill drought stressed turf is when the plant is subject to intense traffic and
the crown is damaged. Those areas likely will not recover from that abrasive
stress of heavy foot traffic or wheel traffic. Therefore, avoid heavy use
during this drought period.

What if I need to replant?

The plus side of all of this is there is a lot of time to plan for
a better lawn for the future (generally mid-August is the suggested time to
begin turf seeding for the cool-season turf species (e.g. ryegrasses, fescues,
bluegrasses). If you lawn does severely thin or large areas do not survive this
is a perfect opportunity to replant with an improved species or
cultivar/variety.

This area has severely thinned and may require replanting.

One group that I am collaborating with is the Turfgrass Water
Conservation Association (TWCA: http://www.tgwca.org/). The stated mission of
this organization is “The main goal of the TWCA program is to combat the rising
concern of our depleting water resources. To accomplish this goal, the TWCA
program is designed to recognize plants and other live goods products in the
lawn and garden industry that provide a clear benefit in water conservation.
Products that become TWCA qualified will have successfully met a stringent set
of criteria.” In this program we are testing and learning about new
varieties of various common lawn grass species that are most drought tolerant.
Several new very drought tolerant cultivars are listed on the program’s
website. One characteristic of these varieties compared to prior generations
are these grasses are simply are able to retain their green color for a much
longer period of time even though they are drought stressed.
Additionally, I participate with another species/cultivar evaluation
program, the National Turfgrass Evaluation Program (NTEP) http://www.ntep.org/ This organization also has information
regarding the relative drought tolerance of many commercially available
cultivars.

If you need to replant immediately, Sodding damaged areas is
certainly another option, but the availability of the aforementioned drought
tolerant cultivars may be limited. Furthermore, unless it can be regularly
watered, it may not survive.

What about fertilizing?

One of the suggested water conservation practices is to stop or
reduce (decrease amount) nitrogen fertilization during periods of drought.
There is no need to push shoot/leaf growth in the plant when other resources
like water are limited. Hence, if your lawn is brown and “crunchy”, certainly
do not fertilize at this time.

The partial silver lining…

The upside to this very slow growth and dry conditions is that drought
stressed turf does not grow vigorously and thus will require fewer mowings.
Furthermore, turfgrass disease incidence is also very low.
Consider the current state of your lawn a “more sustainable” turf cover.

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10
comments:

Your lawn really gets stressed out during drought season, but there are still ways to bring your lawn back to life. One important thing that you need to remember is that you have to wait for the right time. “…if your lawn is brown and “crunchy”, certainly do not fertilize at this time.”---Yes, because the grass will not respond to any fertilizers. You just have to wait for the rainy season. Grass has a natural ability to recover, so you just have to give your lawn the proper care that it needs for it to look good again and stay healthy.

Historians believe the word lawn comes from the Celtic “lan/llan/laun,” which means enclosure. It is thought that lawns began as grassed enclosures within early medieval settlements. Before lawn mowers were invented – or mowing machines, as they were first called – lawns were cut by scything and shearing, much as grazing pastures are sometimes cut today. This method was so labor intensive that only the very rich could afford to maintain lawns .

This is an awesome guide. Definitely worth looking into for people who like to maintain their turf as green and healthy as it can be. While I do water my lawn, I usually do it only once, possibly twice a week if it seems like it needs it. It’s not the greenest lawn you’ll see, but at least it’s not going all brown on me.

Most likely, though you should know that you have to water your lawn, unless it gets water from some nearby or underground source. In any case, now you'll be needing some turf. May I suggest turf in Vancouver?

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